President Moon Jae-in pledged Thursday to maintain close partnerships with the new US administration, chairing a rare plenary session of the National Security Council (NSC) hours after Joe Biden's inauguration.

"The government will develop the South Korea-US alliance as a more comprehensive and mutually beneficial one," he said at the outset of the session held at Cheong Wa Dae, which was briefly open to pool reporters.

Moon also said his government will make utmost efforts to restart dialogue and cooperation with North Korea.

He stressed that the peace process is a must, not an option, and called on his national security team to do its best to end a longstanding stalemate in Washington-Pyongyang talks and inter-Korean dialogue at an early date.

Moon regarded the Indo-Pacific region as entering a "rapid transition period" and stressed that it is time to strengthen the Seoul-Washington alliance and further develop cooperative ties with neighboring nations.

He noted that South Korea and its largest trading partner, China, will commemorate the 30th anniversary of the establishment of their diplomatic relations in 2022.

"We will have to build a foundation (for the two sides) to move toward a developed relationship," he said.

On Japan, he said, Seoul and Tokyo should "not stay in the past" and need to push for forward-looking relations.

In particular, the Tokyo Olympics, scheduled to take place later this year, could serve as a chance for improvement in Seoul-Tokyo ties and progress in efforts to promote peace in Northeast Asia, he added.

It was the first known NSC meeting chaired by Moon in nearly two years. He convened the previous one to discuss a strategy following the no-deal Hanoi summit between the leaders of the US and North Korea in late February 2019.

Moon also received a report from the foreign, defense and unification ministries on 2021 policy direction and goals. (Yonhap)